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A062081
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Group the even numbers as (2,4), (6,8,10,12), (14,16,18,20,22,24), (26,28,30,32,34,36,38,40), ... then a(n) = LCM of the n-th group.
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1
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4, 120, 55440, 42325920, 7210803600, 43790142876480, 6338767304469600, 659267412349963697280, 1688424674909818263818400, 2043724034861836818744052800, 9347568224452825219277416992000
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OFFSET
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1,1
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LINKS
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EXAMPLE
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a(2) = lcm(6,8,10,12) = 120.
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MATHEMATICA
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Table[LCM@@(2*Range[1-n+n^2, n+n^2]), {n, 15}] (* Harvey P. Dale, Jul 18 2015 *)
Module[{nn=11, tl}, tl=TakeList[Range[2, 2nn+(2nn)^2, 2], Range[2, 2nn, 2]]; LCM@@@ tl] (* Harvey P. Dale, Jan 29 2023 *)
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PROG
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(PARI) for(n=1, 20, p=1:forstep(k=2*(n^2-n+1), 2*(n^2+n), 2, p=lcm(p, k)):print1(p", "))
(PARI) { for (n=1, 100, a=b=2*n^2 - 2*n + 2; for (k=1, 2*n - 1, a=lcm(a, b + 2*k)); write("b062081.txt", n, " ", a) ) } \\ Harry J. Smith, Jul 31 2009
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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